Prophylactic immunization to Helicobacter pylori infection using spore vectored vaccines
Paidamoyo M. Katsande, Van Duy Nguyen, Thi Lan Phuong Nguyen, Thi Kim Cuc Nguyen, Gabrielle Mills, David M. D. Bailey, Graham Christie, Huynh Anh Hong, Simon M. Cutting- Infectious Diseases
- Gastroenterology
- General Medicine
Abstract
Background
Helicobacter pylori infection remains a major public health threat leading to gastrointestinal illness and increased risk of gastric cancer. Mostly affecting populations in developing countries no vaccines are yet available and the disease is controlled by antimicrobials which, in turn, are driving the emergence of AMR.
Materials and Methods
We have engineered spores of Bacillus subtilis to display putative H. pylori protective antigens, urease subunit A (UreA) and subunit B (UreB) on the spore surface. Following oral dosing of mice with these spores, we evaluated immunity and colonization in animals challenged with H. pylori.
Results
Oral immunization with spores expressing either UreA or UreB showed antigen‐specific mucosal responses (fecal sIgA) including seroconversion and hyperimmunity. Following challenge, colonization by H. pylori was significantly reduced by up to 1‐log.
Conclusions
This study demonstrates the utility of bacterial spores for mucosal vaccination to H. pylori infection. The heat stability and robustness of Bacillus spores coupled with their existing use as probiotics make them an attractive solution for either protection against H. pylori infection or potentially for therapy and control of active infection.